The recent fields layout update broke a selector for the issue summary

table. Some assumptions were made about the placement of the

.rb-c-issue-summary-table element, which broke. This in turn broke the

filters, tabs, and other behavior.
This change fixes the selector, restoring all functionality, and adding

an assertion so this is caught in the future.

Tested behavior on desktop and mobile. Verified I could filter by users

and by status again.